Adjustable woven filtering material having angularly disposed guide lines



Filed April 17, 1967 2 Sheets-Sheet 1 May 14, 1968 HELLAND ET 3,382,979

ADJUSTABLE WOVEN FILTERING MATERIA ING ANGULARLY DISPOSED GUIDE LIN 6 /5A! Q? A? will"!!! 'llllll lllllflfllll.

HOWARD M llaulvo [CR/1% H ORB/50M INVENTORSI May 14, 1968 M, HELLAND ETAL 3,382,979

ADJUSTABLE WOVEN FILTERING MATERIAL HAVING ANGULARLY DISPOSED GUIDELINES Filed April 17, 1967 2 Sheets-Sheet 2 OHM mw; s 5; ma A mm; Mn

United States Patent O 3,382,979 ADJUSTABLE WOVEN FILTERING MATERIAL{IAVIglG ANGULARLY DISPOSED GUIDE INE Howard M. Helland and Frank H.Orbison, Appleton, Wis., assignors to Appleton Mills, Appleton, Wis., acorporation of Wisconsin Filed Apr. 17, 1967, Ser. No. 631,380 11Claims. (Cl. 21091) ABSTRACT OF DISCLOSURE A woven fabric, such as apapermakers felt, composed of a series of generally parallel warp yarnsand a series of cross yarns which are disposed at an acute angle withrespect to a line normal to the warp yarns and are freely adjustablewith respect to a line normal to the warp yarns and are freelyadjustable with respect to the warp yarns. The endless felt is providedwith a pair of guide lines, with one of said guide lines extendingtransversely between the Side edges of the felt and the second guideline being disposed at an acute angle to the first guide line andlocated in alignment with the cross yarns. The transverse guide line isused to set up and maintain alignment of the felt on the papermakingmachine, while the diagonal guide line provides an indication of theangularity of the cross yarns.

In a papermaking machine, the papermakers felt is utilized to pick up orreceive a freshly laid web of Wet paper after it leaves the forming wireand conduct the paper web through the pressing operation whereadditional water is removed from the wet paper web. For effectiveoperation, the highest possible rate of water drainage through the feltand the requisite surface smoothness of the paper being made must beprovided and sustained over the longest possible period of time in orderto produce the maximum useful felt'life. Purther, the papermakers feltmust have a high degree of dimensional stability and the physicalproperties of the felt must be uniform throughout its dimensions so thatthe paper is uniform in quality and finish.

The copending patent application of Howard M. Helland, entitledAdjustable Woven Fabric, Ser. No. 631,- 381 filed Apr. 17, 1967, nowabandoned in favor of continuation-in-part application Ser. No. 676,370,filed Sept. 27, 1967 discloses aniimproved papermakers felt in which thecross yarns are located at an acute angle with respect to the warp orlongitudinal yarn, and can be adjusted in angula-rity when the felt ison the papermaking machine to vary the drainage rate of the felt and thefinish characteristics of the paper. The adjustable felt of this typeincludes a series of generally parallel warp yarns which are disposedlongitudinally of the direction of travel of the felt. A series ofgenerally parallel cross yarns are interwoven with the warp yarns andare subsequently skewed or cocked to position the cross yarns at anacute angle up to 80 .with respect to a line normal to the warp yarns.Thereafter the felt is stabilized in the skewed position. Afterinstallation on the papermaking machine, the angularity of the crossyarns can be adjusted from the original skewed position to vary thedrainage characteristics of the felt and the nature of the finish of thepaper.

According to the present invention a pair of guide lines or markers areapplied to the endless felt. One of the guide lines extends transverselybetween the side edges of the felt, while the second guide line islocated at an acute angle with respect to the first guide line and isdisposed in alignment with the angularity of the cross yarns.

An adjustable felt in which the cross yarns can be adjusted inangularity with respect to the warp yarns has distinct advantages indrainage, service life and finish characteristics of the paper. Thepresent invention, by incorporating a pair of guide lines with the feltas installed on a papermaking machine, provides additional advantages tothe papermaker.

The transverse guide line, which for felts of conventional constructionextends normal to the side edges of the felt, and is aligned with thecross-machine yarns, enables the papermaker to properly set up themachine and maintain the desired alignment of the felt on the rollsduring the papermaking operation.

If the felt is allowed to skew or how while operating on the papermachine, the operating characteristics of the conventionally designedfelt are adversely affected. The transverse guide line enables thepapermaker to visually determine whether the felt is skewed or bowed,and by proper adjustment of the rolls, the felt can thereby bemaintained in its designed configuration.

The diagonal or cross yarn guide line of the invention provides a visualindication to the papermaker of the angular disposition of the crossyarns of the adjustable woven felt and thereby enables the papermaker tomore readily adjust the angularity of the cross yarns to the desiredvalue for the particular operation. For example, by adjusting theangularity of the cross yarns with respect to the warp yarns when thefelt is on the papermaking machine, the relative size of the openings orpassageways between the yarns can be altered to thereby vary thepermeability and drainage characteristics of the felt as desired. Thecross yarns may also be adjusted to compensate for the gradual closingup of the felt due to the accumulation of fines or other contaminantsfrom the paper in the woven structure as well as structural compactiondue to the continuous application of pressure. In both cases, thediagonal guide line provides a continual visual indication of theangularity of the cross yarns and correspondingly indicates the degreeof openness of the felt structure.

In other instances the angularity of the cross yarns may be adjustedwhile the felt is on the papermaking machine to vary the finishcharacteristics of the paper. Adjusting the cross yarns varies thedegree of openness of the felt structure and thereby willcorrespondingly change the finish characteristics of the paper. Again,the diagonal guide line enables the papermaker to see the angulardisposition of the cross yarns and aids him in setting the angularity toa predetermined value designed for a given paper finish.

The papermaker may also wish to adjust the angularity of the cross yarnsof the felt to open up the woven felt structure and recondition andclean the felt during the time that the felt is outside of the nip, andwith the use of the diagonal guide line the papermaker can readilydetermine when the felt is in the maximum open condition.

As a further advantage, the transverse guide line and the diagonal guideline cooperate to provide a more exaggerated indication of bowing of thefelt on the machine and this aids the operator in maintaining the feltin the designed configuration for the particular operation.

Other objects and advantages will appear in the course of the followingdescription.

The drawings illustrate the best mode presently contemplated of carryingout the invention.

In the drawings:

FIGURE 1 is an enlarged fragmentary plan view of the papermakers feltshowing the orientation of the warp yarns and the cross yarns;

FIG. 2 is a diagrammatic side elevation of a typical press section of apapermaking machine employing the felt of the invention;

FIG. 3 is a plan view showing the felt as supported on the paperrnakingmachine with the cross yarns positioned at an angle of about 45 withrespect to a line normal to the warp yarns;

FIG. 4 is an enlarged plan view showing the fiber orientation of thefelt of FIG. 3;

FIG. 5 is a view similar to FIG. 4 showing the cross yarns adjusted toan angle of about 0 with respect to a line normal to the warp yarns; and

FIG. 6 is an enlarged plan view showing the fiber orientation of thefelt of FIG. 5.

FIG. 1 illustrates a woven fabric which is particularly adaptable foruse as a papermakers felt. The fabric or felt 1 comprises a series ofgenerally parallel warp yarns or strands 2 and a series of generallyparallel cross yarns or strands 3 which are disposed at an acute anglewith respect to the warp yarns. The cross yarns 3 are interwoven withthe warp yarns 2 and are freely adjustable in angularity with respect tothe warp yarns.

The yarns or strands 2 and 3 can be formed of any fibrous, monofilamentor multifilament material. For example, the strands 2 and 3 may becomposed of animal fiber such as wool; vegetable fibers such as cotton;mineral fibers such as glass; synthetic fibers such as Dacron, Orion ornylon; or metal fibers such as steel wire. De pending on the nature ofthe fabric and its ultimate use, mixtures or blends of the above fiberscan also be employed. When the invention is utilized as the papermakersfelt, wool fibers, synthetic fibers or blends thereof are comm-onlyused.

The felt or fabric 1 can be fabricated in the manner described in thecopending application of Howard M. Helland, Ser. No. 631,381 filed Apr.17, 1967, and now abandoned in favor of continuation-in-part applicationSer. No. 676,370, filed Sept. 27, 1967. The felt 1 is either woven inendless form, or alternately, a straight length of felt can be handspliced by conventional techniques to provide the endless form.Following splicing, or if the felt is woven in endless form, the felt iscocked or skewed, resulting in the cross yarns being moved to an acuteangle with respect to the warp yarns, as shown in FIG. 1, and thecocking correspondingly brings the warp yarns closer together with theeffect that the overall width of the felt is decreased. The felt can becocked either manually or by positioning the felt over a pair of spacedstretch rolls. While trained over stretch rolls, one side of the felt isurged in one direction while the other side is urged in the oppositedirection to thereby cock or skew the cross yarns. The manner of cockingthe felt is not critical to the invention and any method can be employedwhich will adjust the angularity of the cross yarns with respect to thewarp yarns to the desired degree.

As disclosed in the aforementioned application of Howard M. Helland, thecross yarns are cocked or skewed at an angle up to 80 with respect to aline normal to the warp yarns 2 and in most cases the cross yarns areskewed to an angle of to 70, with an angle of about to 60 beingpreferred. In the uncooked state the openings or spaces between thestrands 2 or 3 are generally rectangular in shape, while after cockingthe openings between the strands have an elongated, parallelogram shapeas shown in FIG. 2.

After cocking, the felt is stabilized according to conventionalprocedures. Various methods may be used to stabilize the felt and theprocedures to be employed are generally determined by the composition ofthe felt and the ultimate use of the felt in the papermaking process.Stabilization, for example, can be carried on by needling, heat setting,chemical setting or by heat and moisture fulling.

The cocked and stabilized felt can be installed on a press of a typicalpapermaking machine as shown in FIG. 2. The endless felt 1 is supportedfor movement on a series of rolls 4, '5, 6, 7, 8 and 9. After the felt 1leaves the roll 9, a wet web of newly formed paper 10 is transferredfrom the Fourdrinier wire, not shown, to the upper surface of the feltand the felt and wet web of paper 10 pass between a pair of press rolls11 and 12 where the roll pressure serves to extract water from the paperweb. The partially dried paper sheet is then transferred from the feltto a second web, not shown, which carries the partially dried paper webto further drying means.

The felt I can be adjusted while on the papermaking machine to vary theangularity of the skewed or cocked cross yarns and therebycorrespondingly vary the drainage rate of the felt and finishcharacteristics of the paper. To provide for an adjustment of angularityof the cross yarns of the felt, the ends of the shaft 13 of roll 6 arejournaled within bearing blocks 14 which are pivotally connected to nuts15 and jack screws 16 are threaded with the nut 15. By rotation of thejack screws 16, the axis of the roll can be varied in angularity. Theangular adjustment of roll 6 has the effect of causing warp yarns totravel successively greater distance in each revolution of endlesstravel of the felt with a resultant reorientation of the cross yarns 3relative to warp yarns 2. When the desired degree of angular adjustmenthas been achieved, the adjustable roll 6 is returned to its Originalposition and the new angularity of the cross yarns is maintained untilfurther adjustment. An adjustable roll is provided on all standard papermachines to maintain the felt in its designed configuration, and theadjustable roll can also be utilized to adjust the angularity of thecross yarns with respect to the warp yarns while the felt is on themachine.

IIl'ZtCCOl'dZlHCfi with the invention, a guide line or marker 17 isapplied to the felt 1 and extends transverse to the side edges of thefelt. In addition to the guide line 17, a second guide line 18 isapplied to the felt and extends in alignment with the cross yarns. Theguide line 17, which is not located in alignment with either the warpyarns or the cross yarns, can be applied to the felt with a conventionaldye, while guide line 18, which is located in alignment with the crossyarns, can be Woven into the felt during the weaving process or can beapplied to the felt with dye as in the manner of guide line 17.

While it is preferred that the guide line 18 intersect the guide line 17adjacent the side edge of the felt, as shown in FIG. 3, the guide line18 can also intersect the guide line 17 along the mid portion of thelength of the guide line 17, or the guide line 18 can be spaced from theguide line 17. If the guide line 18 is spaced from the guide line 17,the two guide lines should, however, be located in the same portion ofthe felt so both will be visible to the operator at the same instantduring endless travel of the felt.

It is also contemplated that one of the guide lines can be one color,while the other guide line can be a different and contrasting color.This color distinction would enable the papermaker to instantlyrecognize which of the guide lines was the normal guide line 17 andwhich was the cross yarn guide line 18, regardless of the angulardisposition of the two guide lines.

The normal guide line 17 aids the papermaker in determing whether thefelt is in the desired configuration on the rolls. In the event theguide line 18 shows a skew or how, the papermaker can adjust the roll 6to bring the felt back to the desired configuration. The guide line 13serves as an indication of the disposition of the cross yarns 3 and thepapermaker can readily adjust the angularity of the cross yarns to thedesired value by viewing the guide line 19. For example, FIG. 3 showsthe felt 1 installed on the papermaking machine and running in whatwould be a normal condition for the particular felt. In this instance,the guide line 17 is positioned normal to the side edges of the felt andto the warp yarns 2, while the guide line 18 is located at an angle ofabout 45 with respect to the guide line 17, in alignment with crossyarns 3, as shown in FIG. 4, which illustrates the fiber orientation. Byadjusting the roll 6 to the position shown in FIG. 5, the cross yarns 3and guideline 18 will be moved to a position normal to the side edges ofthe felt, and in this position the felt will have its most openstructure. Adjusting the angularity of the cross yarns from the positionof FIG. 3 to the position of FIG. 5 will correspondingly move the warpyarns further apart and increase the overall width of the felt. In theopen position of FIG. 5, the guide line 17 is disposed at an acute anglewith respect to the side edges of the felt, but the guide lines 17 and18 have the same angular relationship to each other as in the positionof FIG. 3.

Conversely, by adjusting the angularity of the roll 6 in the oppositedirection from that shown in FIG. 5, the cross yarns and guide line 18will be moved to an angle greater than 45 with respect to a line normalto the side edges of the felt, and the guide line 17 will extend at anacute angle with respect to the side edges of the felt.

While the above description was directed particularly to the use of thefabric of the invention as a papermaker felt, it is contemplated thatthe invention can be used in any application for filtering fluids whereit is desirable to adjust the angularity of the cross yarns with respectto the warp yarns.

Various modes of carrying out the invention are contemplated as beingwithin the scope of the following claims particularly pointing out anddistinctly claiming the subject matter which is regarded as theinvention.

We claim:

1. An apparatus of the class described, comprising a web formed of aseries of generally parallel first strands and a series of generallyparallel second strands interconnected with the first strands, saidsecond strands being located at an acute angle up to 80 with respect toa line normal to said first strands and being freely adjustable withrespect to said first strands, a first guide line applied to the web andextending from One edge of the web toward the opposite edge thereof, anda second guide line applied to the web and extending from one edge ofthe web toward the opposite edge of the web and being disposed ingeneral alignment with the second strands, said second guide line beingdisposed at an acute angle with respect to the first guide line.

2. The apparatus of claim 1, wherein said second guide line intersectssaid first guide line.

3. The apparatus of claim 1, wherein said second guide line intersectssaid first guide line adjacent the side edge of the web.

4. The apparatus of claim 1, wherein said web is ende 1 less and saidfirst strands are disposed longitudinally of the web.

5. The apparatus of claim 4, wherein said edges are longitudinal sideedges of the endless web.

6. An apparatus for filtering fluids, comprising an endless web, websupporting means for supporting the web in endless travel, said webincluding a series of generally parallel spaced first strands disposedlongitudinally of the direction of travel of the web and including aseries of generally parallel spaced second strands, said second strandsbeing interwoven with said first strands and being freely adjustable ina-ngularity with respect to said first strands, said second strandsbeing disposed at an acute angle up to with respect to a line normal tosaid first strands, adjusting means for adjusting the angularity of thesecond strands with respect to the first strands when the web issupported for endless travel, a first guide line applied to said web andextending across said web and extending at an acute angle to both saidfirst strands and said second strands, and a second guide line appliedto the web and disposed in general alignment with said second strands.

7. The apparatus of claim 1 in which said second guide line is adifferent color than said first guide line.

8. The apparatus of claim 6, wherein the guide lines are disposed at anangle of about 45 to each other.

9. The apparatus of claim 6, wherein the first guide line is disposed atabout to the side edges of the web during normal operation of said web.

10. A papermakers felt, comprising a series of generally parallel warpyarns, a series of generally parallel cross yarns engaged with saidrespect to said being freely adjustable in angularity with respect tosaid warp yarns, said warp yarns and cross yarns defining a plurality ofopenings therebetween, said cross yarns being located at an angle up to8-0 with respect to a line normal to said warp yarns and beingadjustable with respect to the warp yarns to thereby vary the effectivesize of said openings and vary the drainage rate of the felt and thefinish characteristics of the paper, a first guide element disposed on asurface of the felt and extending across the felt between opposite sideedges thereof, and a second guide element disposed on said surface ofthe felt and extending across the felt and disposed in general alignmentwith said cross yarns, said second guide element being disposed at anacute angle to said first guide element.

11. The paperrnakers felt of claim 10, wherein said felt is in endlessform and said first guide element is disposed at an angle of about 90 tothe side edges of the felt during normal operation of said felt on apapermaking machine.

No references cited.

SAMIH N. ZAHARNA, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,387,979

Howard M. Helland et al.

May 14, 1968 It is certified that error appears in the above identifiedpatent and that said Letters Patent are hereby corrected as shown below:

M Column 6, line 32, "respect to said" should read warp yarns and Signedand sealed this 14th day of October 1969.

(SEAL) Attest:

WILLIAM E. SCHUYLER, JR.

Edward M. Fletcher, Jr.

Attesting Officer Commissioner of Patents

